1/29/2009 @ 6:30PM

Great Wines Under Cork And Screw Cap

Admit it: The first time you saw a wine bottle with a screw top, you thought it was only slightly better than that found in a box. But if the wine had a cork, well, that was a trademark of quality, right?

Fair enough. But if you still feel that way about your wine purchases, you haven’t been paying much attention to what you’re drinking. The fact is, screw caps have topped bottles from some of the world’s best wineries for about a decade, and even the most reputable wine critics openly acknowledge that there’s nothing wrong with sealing a wine bottle with a screw cap in lieu of a cork. In fact, thousands of brands prefer the former.

Why the change? The first problem is that corks are formed inconsistently by Mother Nature (they’re tree bark, after all), and therefore some allow in significant amounts of air that can spoil the wine. What’s more, a chemical called 2, 4, 6 trichloroanisole can leak from the cork into the wine, ruining the aromas and flavors by making them smell like wet newspapers or cardboard.

But is a screw cap the perfect solution to both problems? We asked George Taber, author of To Cork Or Not To Cork: Tradition, Romance, Science and the Battle for the Wine Bottle to clarify.

Switching from corks to screw caps is a tough decision for a winery, in a business that had a value of $150 billion globally in 2007, according to IWSR, a London-based market research firm. Never mind that expensive bottling equipment might need to be purchased; how might loyal, longtime consumers react to having a bottle with a cork one day and a screw cap the next?

That’s why some producers, like Napa winery Plumpjack, with its Oakville cabernet sauvignon, have treaded carefully. Starting in 1997, this winery switched only half its 3,000-plus case production to screw cap and keeps half under cork (depending on the growing season and crop yields, Plumpjack says it averages about 5,000 cases per year of this wine).

The hesitancy by some, Taber believes, is warranted. A screw cap is problematic in that it’s a perfect, air-tight seal. Sometimes a wine can have an unpleasant aroma–oftentimes caused by hydrogen sulfide, a byproduct of the fermentation process–that is completely trapped inside a screw-capped bottle. A cork, porous by nature, might let the unwanted aroma leak out.

Screw-cap advocates argue that the off-putting smell can be eliminated simply by emptying the wine into a decanter. But the existence of the problem is evidence enough for Taber to conclude that neither screw caps nor corks are perfect and, therefore, it’s up to you, the wine drinker, to decide for yourself–over time and from your own wine-tasting experiences–which you prefer and trust.

Unfortunately, so few wines are available under both cork and screw cap, as Plumpjack is. But trying the two side by side, blind, as we did, might be a good first step toward figuring out which your taste buds prefer because, much to our surprise, there was a significant difference.

Which wine was better? It came down to a simple matter of taste, which is really what the argument should be about anyway–and will be, should someone ever truly find the perfect seal for a wine bottle. Some say a screw cap is the next best thing; others say we still have a long way to go.